Compressor Off?

[George Clark]

Attached are photos of a failure of a combination regulator, filter and water trap in my shop air system. Fortunately, I was in the shop when it failed. It sounded like a shotgun blast when it let go. This was an ARO unit that I installed new. The line pressure had never exceeded the rated pressure of the unit. All four of the locking lugs on the regulator body failed.

The point of my post is not to degrade ARO, parts fail, but to encourage you shut your compressors off when you leave the shop. Had I been away from the shop with the compressor on, it would have run continuously until the compressor seized (bad) or things got so hot that the shop caught on fire (really bad).

I had a similar failure about 20 years ago when an air hose fitting failed on my relatively new compressor. I was at home but away from the shop. My wife mentioned that the compressor had been running for a long time. When I went to investigate the compressor was still running but extremly hot. When things cooled the pump was seized and required a complete overhaul at a cost that almost exceeded the cost new. Lesson learned.

George
0032620

 

[Vaughn]

Good reminder, George. I saw photos recently of a compressor that had run until it caught fire. That convinced me to start being more consistent about turning the compressor off when I leave the shop.

 

[MichaelMouse]

Thing is, you forget it when (because) it's not running. There are a lot of good reasons for having a whole shop cutoff. That's one, (grand)kids are another.

 

[Leo Frilot]

I also witnessed the same problem, twice. Once with the water knockout pot failing and once with the piping failing. Both times I was in the shop. My compressor has a high temp cutoff that worked both times, but cutting the power would be a better solution. Thanks for the reminder to cut power.

 

[Steve Worcester]

Put a ball valve right at the compressor's out pipe and turn that off. Yes, you will have it turn off it there are leaks in the compressor itself, but it won't turn on otherwise.

 

[John Van Domelen]

turn off and drain

I have a 220v 60 gal Ingersoll Rand Compressor (shameless plug - I love this thing - some of the best $$ I ever spent) that I am in the habit of both turning off and draining at the end of a day working in the studio.

Here in Houston, with our humid air - there is quite a bit of water in the bottom of the tank at the end of the day. Draining the unit prevents rust in the tank long term, or so I have been told.

 

[hughie]

My compressor is a bit noisy and so irritating, I have often thought about muffling the noise. But because of the noise I never fail to turn the thing off 😀

 

[Steve Worcester]

..Here in Houston, with our humid air - there is quite a bit of water in the bottom of the tank at the end of the day. Draining the unit prevents rust in the tank long term, or so I have been told.

And lessens water in suspension in the air in the tank

 

[Mark Mandell]

Compressor Condensate

I have a 220v 60 gal Ingersoll Rand Compressor (shameless plug - I love this thing - some of the best $$ I ever spent) that I am in the habit of both turning off and draining at the end of a day working in the studio.

Here in Houston, with our humid air - there is quite a bit of water in the bottom of the tank at the end of the day. Draining the unit prevents rust in the tank long term, or so I have been told.

Make it much easier on yourself by having your compressor drain the water automatically. Go to the McMaster-Carr website and enter item number 4919K13 in the search box. This is a $50 air-activated valve that purges the condensate with a 10-20 psi drop in pressure; usually once in each cycle.

I have the same compressor with valve installed and it has worked beautifully for 5 years. The only maintenance is to clean and regrease the valve's piston once or twice a year depending on use. This is easy to do if you install a 1/4" ball valve upstream from the auto-drain so that you can depressurize the valve without draining all of the tank's pressure.

 

[John Jordan]

A timely post. Three days ago I walked into a shop that was HOT from a broken pipe and the continuously running compressor. Like John Van D, I have a nice Ingersoll-Rand, (mines bigger, though 😀). It really made me think. I turn the valve at the tank off when I'm leaving town, but will try from now on to turn it off daily. It could have been bad-or devastating...........

FWIW, I use an auto drain that works from pressure change, so it drains in short bursts all through the day-I really like it.

John

I see Mark posted about the same time I did. I believe he's the one that turned me on to the drain. 🙂

 

[Steve Worcester]

I have an auto drain too, but since there is air in the tank all the time, and it doesn't get used every day, I still do a quick drain on occasion.

 

[Mark Mandell]

No substitute for safety when it comes to automatic machinery. Every compressor has an "off" switch which should be used when leaving the shop "for the day."

If the compressor is installed in a piping system, this also provides a useful check on leaks in the fittings. Note the tank pressure when you leave, then check it when you come back. A change of more than 5 psi (without a significant temperature change in the shop) suggests that you should check for leaks. No sense in paying the money to pump all that air if you're going to let it pssssss away. Since I have a branch for my basement shop and another for the garage (where the compressor is installed), I piped each with a cut-off valve so I can isolate each branch for repairs or additions without a full depressurization.

An electrician told me about a safety timer that will cut off power to a compressor if it runs for too long at a stretch. Haven't been able to find one yet.

 

[Bill Boehme]

A couple years ago, my compressor air hose had a blowout when I was not in the shop and the compressor ran continuously for at least 12 hours before I discovered it. The shop was filled with white smoke from burning oil and the compressor was as hot as a wood burning stove.

At first, I thought that the shop was on fire. I was really surprised by how hot the compressor was and because of the heat, I could not get close enough to pull the plug. I went back outside, got a breath of fresh air and then went back and shut off everything in the breaker panel.

Later, I found that the compressor still had usable compression, but I suspect that the rings probably had a lot looser fit than before. Before this failure occurred, I noticed a small aneurysm in the sidewall of the air hose, but foolishly ignored it.

Now, I make sure that power to the compressor is off before leaving the shop. There was enough flammable material around the compressor that it is possible that a fire could have started.